" Is this fair?"
Yes.
I'll explain why.
This is fair because we're already following the rules. So, it won't make an iota of change to us, already rule followers. However, it will incriminate and stop those who don't care about the rules, our NHS, peoples lives or their integrity from doing these things. Yes it's a shame they might now stop you from going on walks but I'd rather total lockdown for a couple of weeks rather than what we have now, being endless.